package cn.edu.scau.cmi.liquan.exercise9.Example9_8;

public class EncryptAndDecrypt {
    String encrypt(String sourceString,String password) {
    	char[] p=password.toCharArray();
    	int n=p.length;
    	char[] c=sourceString.toCharArray();
    	int m=c.length;
        for(int k=0;k<m;k++) {
        	int mima=c[k]+p[k%n];
        	c[k]=(char)mima;
        }
        return new String(c);
    }
    String decrypt(String sourceString,String password) {
    	char[] p=password.toCharArray();
    	int n=p.length;
    	char[] c=sourceString.toCharArray();
    	int m=c.length;
    	for(int k=0;k<m;k++) {
    		int mima=c[k]-p[k%n];
    		c[k]=(char)mima;
    	}
    	return new String(c);
    }
}
